Communicating knowledge about energy transition is a challenge of sustainable development. Serious games are a possible approach to explain complex relationships and present them to citizens. This paper discusses the development process of the serious board game “Changing the Game—Neighbourhood”. Therefore, this paper describes our approach of developing a serious game with co-designers in four phases and illustrates the process using an example. Doing so, the paper focus on two central challenges: (1) How can a serious game be developed for the energy transition, which keeps a balance between learning and playability? (2) How can co-design contribute to the development of a serious game? We found out that the use of prototypes and the influence of different stakeholders as informants, co-designers, and testers were crucial for the expansion of the learning content, the improvement of the gameplay, and the balancing of the difficulty level. In addition, the energy transition at the neighborhood level appeared to be a suitable topic for a serious game. During the development process, the serious game was already used for citizen participation, involving about 120 participants in 15 workshops.